Abstract:
In one embodiment, a solid cylindrical tablet is pre-formed for a reflective cup containing an LED die, such as a blue LED die. The tablet comprises uniformly-mixed phosphor particles and transparent/translucent particles of a high TC material, such as quartz, in a hardened silicone binder, where the index of refraction of the high TC material is matched to that of the silicone to minimize internal reflection. Tablets can be made virtually identical in composition and size. The bulk of the tablet will be the high TC material. After the tablet is placed in the cup, the LED module is heated, preferably in a vacuum, to melt the silicone so that the mixture flows around the LED die and fills the voids to encapsulate the LED die. The silicone is then cooled to harden.
Abstract:
A light emitting device (102, 202) comprising a light source (104) having a light exit surface, a wavelength converter (106) configured to convert light from a first wavelength to a second wavelength, said wavelength converter having a light exit surface (110) and a light entrance surface, a heat sink (100) and an optical coupling element (112), arranged in thermal connection with said heat sink (100) and said wavelength converter (106), wherein said optical coupling element (112) is selected to have a refractive index lower than a refractive index of said wavelength converter (106). The optical coupling element (112) will allow for an efficient heat transfer from the wavelength converter (106) to the heat sink (100) while avoiding loss of light from unwanted surfaces.
Abstract:
In an embodiment, a method of making a heat sink assembly (10) can comprise: forming an heat sink assembly (10) comprising a polymer heat sink (14) around a metal insert (12), the polymer heat sink (14) comprising a thermally conductive polymer material, wherein the heat sink assembly (10) has a contact pressure between the polymer heat sink (14) and the metal insert (12); and increasing the contact pressure. In an embodiment, a method of making a heat sink assembly (10), comprises: heating a mold and subsequently introducing a metal insert to the mold, wherein the metal insert has an insert temperature of 30°C to 70°C when it is inserted into the mold; closing the mold; and in less than or equal to 0 seconds of closing the mold, over-molding the metal insert with a thermally conductive polymer material to form a heat sink assembly (10).
Abstract:
Es wird ein optoelektronischer Halbleiterchip (10) angegeben, umfassend : - eine Halbleiterschichtenfolge (20) mit einem ersten Halbleiterbereich (3) eines ersten Leitungstyps, einem zweiten Halbleiterbereich (5) eines zweiten Leitungstyps und einer zwischen dem ersten Halbleiterbereich (3) und dem zweiten Halbleiterbereich (5) angeordneten strahlungsemittierenden aktiven Schicht (4), - eine Strahlungsaustrittsfläche (13), - eine Spiegelschicht (6), welche an einer von der Strahlungsaustrittsfläche (13) abgewandten Seite der Halbleiterschichtenfolge (20) angeordnet ist, - einen ersten und einen zweiten elektrischen Kontakt (11, 12), wobei mindestens einer der elektrischen Kontakte (11, 12) ein Rückseitenkontakt ist, der an einer von der Strahlungsaustrittsfläche (13) abgewandten Rückseite des Halbleiterchips (10) angeordnet ist, und - mindestens eine thermische Anschlussschicht (9), welche an der Rückseite des Halbleiterchips (10) angeordnet ist, wobei die thermische Anschlussschicht (9) elektrisch von der Halbleiterschichtenfolge (20) isoliert ist.
Abstract:
An object of the present invention is to provide a Light Emitting Diode (LED) construction. It is an object of certain embodiments of the present invention to provide an LED Chip-on-Board (COB) construction comprising, a thermally and electrically conductive substrate, at least one semiconductor light emitting die or diode and an electrically insulating material. It is an aspect of certain embodiments that the at least one semiconductor light emitting die bonded to the thermally and electrically conductive substrate. Additionally, the construction comprises an anode or cathode electrode on the insulating material, wherein said anode or cathode electrodes are wire bonded to a first side of the semiconductor light emitting die's electrical contact, and the opposite side of the semiconductor light emitting chip is either anode or cathode. Furthermore, wherein the semiconductor device is encapsulated with an optical encapsulate. The present invention has particular use with red and far red spectrum LED constructions.